400-Mile Deep Ocean Discovery Shakes Up Our Understanding of Earth’s Water”

In a discovery that has surprised the scientific community, researchers have uncovered a vast reservoir of water hidden 400 miles beneath the Earth’s surface.¹ 

As scientists learn more about this remarkable finding, it’s becoming clear that our understanding of Earth’s water cycle and the origins of its oceans may need a major overhaul. Here’s what they found.

A Watery Treasure Trove Hidden in Earth’s Depths

Within the transition zone of Earth’s mantle lies an astonishing discovery—a vast water reservoir locked inside the crystal structure of a mineral called ringwoodite. This deep-Earth sponge can hold up to 1.5% of its weight in water, potentially amounting to a staggering volume that dwarfs all the water in our planet’s oceans.

The presence of this massive water store challenges our understanding of Earth’s composition and raises intriguing questions about the origins of our planet’s water. 

As geophysicist Steve Jacobsen, a key member of the discovery team, put it,

“I think we are finally seeing evidence for a whole-Earth water cycle, which may help explain the vast amount of liquid water on the surface of our habitable planet.”

Ringwoodite: The Unassuming Water Bearer

At the heart of this groundbreaking discovery is a seemingly ordinary mineral with an extraordinary secret. Ringwoodite, a high-pressure form of the mineral olivine, has a unique crystal structure that allows it to attract and trap hydrogen atoms, effectively storing water within its lattice.

This incredible water-bearing capacity of ringwoodite had been theorized for decades, but it wasn’t until 2014 that scientists were able to provide direct evidence of its existence deep within the Earth.^(ref) 

Unveiling Earth’s Secrets through Seismic Waves

To uncover this hidden ocean, scientists employed a network of over 2,000 seismometers strategically placed across the United States.

The study, led by geophysicist Steve Jacobsen and seismologist Brandon Schmandt, combined cutting-edge laboratory experiments with the wealth of seismic data collected by the USArray project. This collaborative approach allowed the researchers to pinpoint the exact depths and locations where water-bearing ringwoodite is likely to exist.

Rewriting the Story of Earth’s Water

The discovery of this massive underground ocean has challenged long-held beliefs about the origins of Earth’s water. The traditional theory suggests that water was delivered to our planet by comets and asteroids during the early stages of its formation. 

However, the presence of such a substantial water reservoir deep within the Earth’s mantle suggests that our planet’s water may have a more complex and ancient history than previously thought.

Implications for Earth’s Dynamics & Habitability

The discovery of this deep-Earth ocean has far-reaching implications for our understanding of plate tectonics and the habitability of our planet:

• Water plays a critical role in the movement of tectonic plates, acting as a lubricant that facilitates their sliding and colliding.
• The presence of water in the mantle can significantly influence the dynamics of plate tectonics, potentially impacting the frequency and intensity of earthquakes and volcanic eruptions.
• The gradual release of water from the mantle over geological timescales could help maintain the delicate balance of Earth’s surface water, ensuring the long-term stability of our oceans and the life they support.

The Search for Global Water Reservoirs

While the discovery of this massive water reservoir beneath the United States is groundbreaking, scientists are eager to determine whether similar reservoirs exist on a global scale.

The research team plans to gather seismic data from around the world to investigate if the presence of water-bearing ringwoodite is a widespread phenomenon.

If these deep-Earth oceans are found to be a common feature of our planet’s interior, it could revolutionize our understanding of Earth’s water cycle and its potential for harboring life. 

A New Frontier in Earth Science

Key Takeaways

• A vast reservoir of water, estimated to be three times the volume of Earth’s surface oceans, has been discovered 400 miles beneath the Earth’s surface.
• The water is trapped within the crystal structure of the mineral ringwoodite, which can hold up to 1.5% of its weight in water.
• This discovery challenges traditional theories about the origins of Earth’s water and suggests a more complex and ancient history.
• The presence of this deep-Earth ocean has implications for plate tectonics, Earth’s habitability, and the search for life on other planets.

As researchers continue to unravel the secrets of this subterranean reservoir, it’s becoming increasingly clear that the story of Earth’s water is far more complex and fascinating than we ever imagined.

From the unassuming water-bearing capabilities of ringwoodite to the hidden water cycle that operates far beneath our feet, this groundbreaking finding has opened up a whole new realm of possibilities in our quest to understand the inner workings of our planet and its potential for harboring life. 

Source:
1. Science